血液透析患者营养状况与逆流行病学现象的探讨

目的 了解维持性血液透析患者(MHD)的营养状况,探讨其存在的逆流行病学现象,为进一步提出针对性营养干预策略提供依据.方法 采用主观综合性营养评估法(SGA)、人体测量、生化指标测定方法综合评估113例维持性血液透析患者的营养状态.结果 根据SGA评分,55.75％(63例)的患者营养状况良好;营养不良患者占44.25％(50例),其中39.82％(45例)为轻-中度营养不良,4.42％(5例)为重度营养不良.营养不良组患者肱三头肌皮褶厚度(TSF)、动静脉瘘对侧上臂周径(MAC)、上臂肌围(MAMC)低于营养良好组,差异有统计学意义(P＜0.01).营养不良组总胆固醇(CH)、三酰甘油(TG)、低密度脂蛋白(LDL)、血清白蛋白(Alb)、前白蛋白(PA)、血肌酐(Scr)、尿素氮(BUN)、钙(Ca)、磷(P)较营养良好组低,其中TG、PA、Scr、BUN差异有统计学意义(P＜0.05,P＜0.01),而高密度脂蛋白(HDL)和甲状旁腺素(PTH)较营养良好组偏高,但差异无统计学意义.结论 MHD患者营养不良发生比例偏高,且MHD患者营养不良是导致其逆流行病学现象的原因之一,建议根据MHD患者具体的病理生理特点来调整治疗标准.     

Influence of polymer molecular weight in osteoinductive composites for bone tissue regeneration

In bone tissue regeneration, certain polymer and calcium-phosphate-based composites have been reported to enhance some biological surface phenomena, facilitating osteoinduction. Although the crucial role of inorganic fillers in heterotopic bone formation by such materials has been shown, no reports have been published on the potential effects the polymer phase may have. The present work starts from the assumption that the polymer molecular weight regulates the fluid uptake, which determines the hydrolysis rate and the occurrence of biological surface processes. Here, two composites were prepared by extruding two different molecular weight l/d,l-lactide copolymers with calcium phosphate apatite. The lower molecular weight copolymer allowed larger fluid uptake in the composite thereof, which was correlated with a higher capacity to adsorb proteins in vitro. Further, the large fluid absorption led to a quicker composite degradation that generated rougher surfaces and enhanced ion release. Following intramuscular implantation in sheep, only the composite with the lower molecular weight polymer could induce heterotopic bone formation. Besides influencing the biological potential of composites, the molecular weight also regulated their viscoelastic behaviour under cyclic stresses. The results lead to the conclusion that designing biomaterials with appropriate physico-chemical characteristics is crucial for bone tissue regeneration in mechanical load-bearing sites.     

联合抽吸导管内注射替罗非班治疗急性ST段抬高型心肌梗死临床研究

目的探讨急性sT段抬高心肌梗死（STEMI）急诊经皮冠状动脉介入治疗（PCI）中联合应用血栓抽吸导管和替罗非班经抽吸导管内注射对心肌组织灌注及临床预后的影响。方法106例急诊PCI治疗的STEMI患者根据治疗情况分为血栓抽吸＋替罗非班组（52例）和单独血栓抽吸组（54例）,比较两组患者手术后即刻梗死相关动脉的心肌梗死溶栓（TIMI）血流、TIMI心肌灌注分级（TMP）。随访30d,比较两组左心室射血分数（LVEF）、住院期间主要心脏不良事件和出血并发症发生率。结果两组基线资料比较差异无统计学意义。术前、术后两组TIMI血流,术前两组TMP差异无统计学意义（P〉0．05）。术后血栓抽吸＋替罗非班组TMP3级率较单独抽吸组明显高（76．2比68．5,P〈0．05）。两组30d随访主要心脏不良事件、LVEF、出血并发症比较差异无统计学意义（P〉0．05）。结论在STEMI急诊PCI中联合使用血栓抽吸导管和抽吸导管内注射替罗非班安全可行,可有效改善心肌组织灌注,且不增加主要心脏不良事件的发生率。     

Sensory phenomena: Clinical correlates and impact on quality of life in adult patients with Tourette syndrome

Tourette syndrome (TS) is a neurodevelopmental condition characterised by multiple tics, with frequent behavioural co-morbidity. Sensory phenomena (SP) are unpleasant sensations which provide involuntary urges to tic in patients with TS. While SP have a central role in tic expression, little is known about their clinical correlates or association with health-related quality of life (HR-QOL) in TS. We conducted a cross-sectional study on 72 adult outpatients with TS, recruited at a specialist clinic. All participants completed a comprehensive battery of psychometric measures, including the Premonitory Urges for Tics Scale (PUTS) to assess SP and a disease-specific quality of life scale (GTS-QOL) to assess HR-QOL. SP were very common (97.2% of patients), with a median PUTS total score of 28/40. Bivariate analyses showed that PUTS scores were most significantly correlated with self-report measures of vocal tic severity and compulsivity. PUTS scores were also significantly correlated with GTS-QOL scores, most notably with the psychological subscale. SP are frequently reported by adults with TS, are associated with perceived tic severity and compulsivity, and can significantly affect psychological well-being. Standardised measurement of SP should be incorporated into routine assessment of patients with TS to optimise their clinical management.     

Rapid visual stimulation increases extrasynaptic glutamate receptor expression but not visual‐evoked potentials in the adult rat primary visual cortex

The model most used to study synaptic plasticity, long‐term potentiation (LTP), typically employs electrical stimulation of afferent fibers to induce changes in synaptic strength. It would be beneficial for understanding the behavioral relevance of LTP if a model could be developed that used more naturalistic stimuli. Recent evidence suggests that the adult visual cortex, previously thought to have lost most of its plasticity once past the critical period, is in fact capable of LTP‐like changes in synaptic strength in response to sensory manipulations alone. In a preliminary study, we used a photic tetanus (PT; flashing checkerboard stimulus) to induce an enhancement of the visual‐evoked potential (VEP) in the primary visual cortex of anesthetised adult rats. In the present study, we sought to compare the mechanisms of this novel sensory LTP with those of traditional electrical LTP. Unexpectedly, we found that sensory LTP was not induced as reliably as we had observed previously, as manipulations of several parameters failed to lead to significant potentiation of the VEP. However, we did observe a significant increase in visual cortex glutamate receptor expression on the surface of isolated synapses following the PT. Both AMPA receptor expression and N‐methyl‐d ‐aspartate (NMDA) receptor subunit expression were increased, specifically in extrasynaptic regions of the membrane, in PT animals. These results provide biochemical confirmation of the lack of change in the VEP in response to PT, but suggest that PT may prime synapses for strengthening upon appropriate subsequent activation, through the trafficking of glutamate receptors to the cell surface.     

Brain‐derived neurotrophic factor/TrkB signaling regulates daily astroglial plasticity in the suprachiasmatic nucleus: Electron‐microscopic evidence in mouse

Synchronization of circadian rhythms to the 24‐h light/dark (L/D) cycle is associated with daily rearrangements of the neuronal‐glial network of the suprachiasmatic nucleus of the hypothalamus (SCN), the central master clock orchestrating biological functions in mammals. These anatomical plastic events involve neurons synthesizing vasoactive intestinal peptide (VIP), known as major integrators of photic signals in the retinorecipient region of the SCN. Using an analog‐sensitive kinase allele murine model (TrkB^F616A), we presently show that the pharmacological blockade of the tropomyosin‐related kinase receptor type B (TrkB), the high‐affinity receptor of brain‐derived neurotrophic factor (BDNF), abolished day/night changes in the dendrite enwrapping of VIP neurons by astrocytic processes (glial coverage), used as an index of SCN plasticity on electron‐microscopic sections. Therefore, the BDNF/TrkB signaling pathway exerts a permissive role on the ultrastructural rearrangements that occur in SCN under L/D alternance, an action that could be a critical determinant of the well‐established role played by BDNF in the photic regulation of the SCN. In contrast, the extent of glial coverage of non‐VIP neighboring dendrites was not different at daytime and nighttime in TrkB^F616A mice submitted to TrkB inactivation or not receiving any pharmacological treatment. These data not only show that BDNF regulates SCN structural plasticity across the 24‐h cycle but also reinforce the view that the daily changes in SCN architecture subserve the light synchronization process.     

Visual phenomena and anatomo-electro-clinical correlations in occipital lobe seizures

BackgroundOccipital lobe seizure are underrepresented in epilepsy surgery cases series. This may reflect the fear for post-surgical functional deficits but also the doubt about the ability of anatomo-electro-clinical correlations to localize precisely the epileptogenic zone in occipital lobe seizure.MethodsIn this expert opinion paper, we review first the general clinical characteristics of occipital lobe seizures, describe the repertoire of visual phenomena and oculo-motor signes in occipital seizures, describe inter-ictal and ictal EEG and finally the possible schemes of epileptogenic zone organization.ResultsVisual and oculo-motor semiology points towards occipital onset seizures but is neither pathognomonic nor constant. Eyes version and unilateral ictal discharge have a strong lateralizing value but inter-ictal spikes as well as eyes version can be falsely lateralizing.ConclusionAlthough visual and oculo-motor phenomena are characteristic of occipital lobe seizures, they may be discrete, overlooked and should therefore be carefully assessed. There are no clear electro-clinical correlations of a sublobar organization of occipital seizures but the clinical pattern of propagation might help to differentiate complex occipito-temporal from occipito-parietal initial epileptogenic network.     

Epileptic and non-epileptic paroxysmal motor phenomena in newborns

Objective: The aim of this study is to provide an extensive overview of the clinical features of neonatal paroxysmal motor phenomena, both self-limited, related to the immaturity of the central nervous system, and pathological (epileptic and non-epileptic), in order to help the diagnostic approach.

Methods: We reviewed the scientific literature about epileptic and non-epileptic paroxysmal motor phenomena in newborns.

Results: Paroxysmal motor phenomena in newborns represent a challenge for the clinicians due to the different underlying pathophysiological mechanisms. A proper differential diagnosis is required.

Conclusions: There are some clinical features that may help clinicians with the differentiation among physiological and pathological, epileptic, and non-epileptic events. However, further investigations are often needed to identify the cause. A continuous synchronized video–electroencephalogram (EEG)–recording, interpreted by an expert in neonatal neurology, remains the gold standard to prove the epileptic origin of a paroxysmal motor phenomenon.     

股骨颈骨折2枚空心螺钉内固定的力学稳定性研究

目的:分析2枚和3枚空心螺钉固定不同骨折线方向的股骨颈骨折的力学稳定性,为2枚空心螺钉临床应用及其适应证的选择提供理论依据。方法:采集15具国人股骨尸体标本,构建3种Pauwels角(30°、50°和70°)的股骨颈骨折模型,分别行3枚及2枚空心螺钉内固定,采用生物力学检测仪分别测定抗张位移、竖向位移、剪切位移、综合位移、缝隙距、扭矩和刚度值,评价2枚和3枚空心螺钉内固定的力学稳定性。结果:Pauwels角为30°和50°时,2枚空心螺钉内固定的抗张位移、竖向位移、剪切位移、综合位移、缝隙距、扭矩和刚度值与3枚空心螺钉内固定相比较,差异无统计学意义(P0.05);当Pauwels角为70°时,采用3枚空心螺钉内固定后,其力学稳定性优于2枚螺钉内固定,差异有统计学意义(P0.05),同时发现Pauwels角为70°时,即使采用3枚空心螺钉内固定,其力学稳定性明显较Pauwels角为30°和50°时差。结论:Pauwels角为30°和50°时,2枚空心螺钉内固定与3枚空心螺钉内固定的力学稳定性相同,2枚空心螺钉内固定已能较好地维持股骨颈骨折的稳定。而当Pauwels角为70°时,3枚空心螺钉内固定力学稳定性则优于2枚空心螺钉内固定,但其力学稳定性较Pauwels角为30°和50°时弱,手术时需采用角稳定系统或者加用抗滑螺钉以增强骨折内固定的稳定性。     

角膜形态学和生物力学参数对角膜后表面高度影响的研究

目的探讨角膜形态学和生物力学参数对近视眼人群角膜后表面高度异常的影响及其辅助诊断角膜后表面高度异常的可行性。方法病例对照研究。选取2017年12月至2018年10月在青岛眼科医院拟行角膜屈光手术的屈光不正患者144例(227只眼),其中男性90例(139只眼),女性54例(88只眼);年龄(22.8±5.6)岁。所有患者检查最佳矫正视力下的球镜和柱镜度数,并行Pentacam眼前节分析系统和Corvis ST角膜生物力学检查。根据Pentacam参数角膜后表面高度变化值(BD)进行分组,将BD<12μm定为对照组(59例,118只眼);将BD≥12μm定为高BD组(85例,109只眼),其中BD≤16μm者为可疑组(44例,53只眼),>16μm者为异常组(41例,56只眼)。选取Pentacam眼前节分析系统中BD、前表面曲率(ASK)、后表面曲率(PSK)、前表面散光(AAstig)、后表面散光(PAstig)、中央角膜厚度(CCT)、角膜直径(W-W)7个参数及Corvis ST角膜生物力学检测系统中第1次压平时间(AT1)、第1次压平长度(AL1)、第1次压平速度(AV1)、第2次压平时间(AT2)、第2次压平长度(AL2)、第2次压平速度(AV2)、最大压陷时间(HCT)、最大压陷峰距(HC-PD)、最大压陷形变幅度(HC-DA)、最大压陷曲率半径(HC-R)、形变幅度比值(DA Ratio)、综合半径、最薄点厚度/厚度变化率(ARTH)、硬度参数(SPA1)、Corvis生物力学指数(CBI)15个参数纳入研究。采用独立样本t检验、Kruskal-Wallis H检验及Bonferroni法进行组间差异性比较,利用Spearman秩相关分析探讨BD的相关影响因素,并建立多元线性回归模型寻找影响BD的主要因素。结果对照组和高BD组在年龄、球镜度数、柱镜度数差异无统计学意义(t=-3.311,-1.808,-2.359;P=0.071,0.072,0.121);Pentacam测量发现在对照组、可疑组和异常组中,ASK、PSK、PAstig、W-W组间差异有统计学意义(Z=18.492,31.547,10.773,70.167;P<0.05),AAstig、CCT组间差异无统计学意义(Z=2.204,1.108;P>0.05)。其中异常组[43.40(42.20,44.40)]较对照组[42.80(41.98,44.00)]ASK增大(t=-4.292;P<0.05),可疑组[-6.50(-6.60,-6.35)]与异常组[-6.50(-6.70,-6.33)]较对照组[-6.30(-6.50,-6.20)]PSK均增大(t=4.492,4.618;P<0.05);可疑组[0.40(0.30,0.40)]与异常组[0.40(0.30,0.40]较对照组[0.40(0.30,0.50)]PAsting均增大(t=2.796,2.515;P=0.016,0.036);可疑组[11.40(11.00,11.60)]和异常组[11.10(10.90,11.30)]较对照组[11.50(11.40,11.80)]W-W减小,同时异常组较可疑组W-W也明显减小(t=3.235,8.353,4.282;P<0.05);Corvis ST参数在3个组间差异无统计学意义(P>0.05)。将每组患者BD与Pentacam参数进行相关性分析发现,在对照组、可疑组、异常组以及所有患者中,BD与W-W呈低至中度负相关(r=-0.614,-0.304,-0.396,-0.661;P<0.05),BD与其他参数相关性较低或未见明显相关性;将患者BD与Corvis ST参数进行相关性分析发现,仅在可疑组中,BD与AV1、HCT、HC-DA间存在低度正相关(r=0.332,0.361,0.382;P<0.05),BD与Corvis ST其他参数在各组中未见明显相关性。以BD为因变量,选取Pentacam参数与Corvis ST参数建立多元线性回归分析模型:变量W-W、ASK、PSK、HC-PD、SPA1、CCT间不存在共线性(容忍度<0.100),方程检验结果F=37.221,P<0.001,调整r^2=0.504,拟合较好。结论角膜形态学参数中角膜直径、前表面曲率、后表面曲率是影响BD的主要因素,角膜生物力学参数中HC-PD和SPA1也可能对BD产生一定程度影响。角膜形态学和生物力学参数的联合评估有助于角膜后表面高度异常的鉴别诊断。